Cita APA (7a ed.)
Codd, E. (1990). The Relational Model for Database Management: Version 2. Addison-Wesley Publishing Company.
Cita Chicago Style (17a ed.)
Codd, E.F. The Relational Model for Database Management: Version 2. New York: Addison-Wesley Publishing Company, 1990.
Cita MLA (9a ed.)
Codd, E.F. The Relational Model for Database Management: Version 2. Addison-Wesley Publishing Company, 1990.
Precaución: Estas citas no son 100% exactas.